Maybe it has something to do with the fact that the game renders ports when your about 30Km from them. Maybe it keeps rendering them after you've left, becuase it seems the game slowed down after visiting three ports. That sinking ships in shallow water makes a lot of sense because I've followed some sinking ships with free look in deep water and they seems to 'disapear' after a certain depth while ships interacting with the ocean floor obvious take up a CPU's time with physics.
|